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Would anyone do me the favor of explaining the overtone system as it pertains to music recording? I'm supposed to explain the system for a homework assignment and the professor has not even mentioned it. Any help is appreciated! -Max

Comments

anonymous Thu, 10/07/2004 - 04:04

what is an overtone system?

I think the implication is "overtone series." Oops, I didn't catch that one.

This was my answer in the the recording forum (I hope I am not doing something wrong by copying it over here):

Overtones or harmonics are what define the quality of a sound or its timbre. Put simply, overtones are whole number multiples of a fundamental. For example: An 'A" is often equal to 440 Hz. It's first overtone would be 880 Hz (440 * 2). The next overtone would be 440 * 3 then next would be 440 * 4 and so on. You could look into Fourier Transform in a math book to find out more info about how to extrapolate the overtones of a complex sound. It has been quite some time since I have delved into the heavy math of Fourier Trasform, but it will help you break a complex sound down into its simpler sine wave components.

As far as how it relates to recording... well, a piano sounds different from an organ playing the same pitch because of the level of each overtone/harmonic in the sound. In fact, some synths create their sounds by varying the level of each overtone to simulate the overtones of the instrument being replicated.

There are a lot of recording effects that are based upon these principles. For example, a convolution reverb uses fourier transform to simplify the sounds so that the computer can recreate the relative reverb levels of a sampled room.

Something else that might help: You could hit a note on a piano and look at an FFT analysis of that note to graphically see what I am explaining here. The FFT should show strength centered at the fundemental (the frequency of the note you played) and varying levels of overtones above that fundamental that make the piano sound like a piano.

Hope I explained this clearly,
Erik

-Erik

Cucco Fri, 10/08/2004 - 06:56

soundfreely wrote: I posted an answer to this question you asked over in the recording studio forum. :)

-Erik

As did I, but here's my posting from the other forum:

Cucco wrote:
Erik is on the right track, but there is more than just whole numbers involved in figuring out the overtone series. Overtones, assuming you are truly hearing the "fundamental" pitch (or lowest pitch intended) are voiced as such:
Overtone 1: 1 octave above fundamental
2: 1 5th above overtone 1
3: 1 4th above overtone 2
4: 1 major 3rd above overtone 3
5: 1 minor 3rd above overtone 4
6: 1 slightly low minor 3rd above overtone 5 (This is a dangerous tone - it's not a real pitch according to Herr Bach.)
7: 1 slightly high major second above overtone 6 (bringing the overtones "back in tune")
8: 1 major second above overtone 7
9: 1 major second above overtone 8
10: 1 slightly low major second above overtone 9 (also a dangerous overtone as it is not a "real" note either)
and so on.... decreasing in interval as you go up.

The overtones are referred to as "partials" and the 1st "partial" is actually the fundamental. So if you want to figure out which partial to refer to, simply add 1 to every overtone number listed above.

Cheers!

J...

Hope this helps...

J... 8-)

anonymous Sun, 10/10/2004 - 15:05

Let's not forget the reason it is critical for an engineer to understand overtones...

If you need to add a bit of bass, you might very well want to boost a few dB in the frequency area of the 1st and 2nd overtones rather than the fundamental frequencies. Knowing how that translates to bandwidth is very important. Otherwise you might add EQ down where there is mostly garbage and the only thing you'll accomplish is causing the clipping in the playback system.

Also, understanding how the overtone series varies between instruments explains why a trumpet sounds different from a horn when playing the same pitch.

A easy thing that instantly demonstrates overtones is to hold a telephone receiver earpiece about an inch from your mouth and change the shape of your mouth by slowly mouthing (not saying) the word "WOW". You should clearly hear about 6 overtones "appear"and "disappear". Now try to consciously note the overtone structure of other instruments and think about how you'd change their sound by EQ or mic choice.

Rich

anonymous Wed, 10/13/2004 - 14:04

radioliver wrote: stop being technical and make good music

If you were being facetious, please ignore the following.

If you were serious, however, then you are in the wrong forum. By the time the goods get to MASTERING it's way too late to do anything but make a mental note to use a different producer next time. Or perhaps decide that it would be wise to spend the money on one rather than buy some more goodies for the "project studio."

Rich

Michael Fossenkemper Wed, 10/13/2004 - 20:08

Sonarerec wrote: [quote=radioliver]stop being technical and make good music

If you were being facetious, please ignore the following.

If you were serious, however, then you are in the wrong forum. By the time the goods get to MASTERING it's way too late to do anything but make a mental note to use a different producer next time. Or perhaps decide that it would be wise to spend the money on one rather than buy some more goodies for the "project studio."

Rich

ouch.

anonymous Mon, 10/25/2004 - 10:09

First of all, it was just a comment to remind us that you can know all you want about the overtone system, a good song is a good song and a bad song is a bad song. It wasn't the right place to post this and I realize a lot of people took this comment personnaly. It wasn't the point. I just want people to know that I realize the importance of "the technical part" of music, otherwise I wouldn't be reading this forum. I just feel that we often go a bit too far in the details and forget about the music. Anyways, I understand it wasn't the right place for this post.

anonymous Mon, 10/25/2004 - 10:19

and by the way, Thomaster, your pilot reference is way off. I'm not saying a guitarist with no hands can play a good song, I'm saying a guitarist with no theory knowledge CAN play a good song. I for one did learn all the theory I could in the little spare time I have, but it doesn't mean someone who never took these courses can't be good. Makes sense?
Your poor analogy tells me enough about you.

anonymous Mon, 10/25/2004 - 10:30

If you guys are through throwing spitballs, consider the the original point-- the overtone system.

And while the music IS the point, the likelihood of a performance that is at the group's real potential in an efficient and successful manner is usually the producer's job, so don't forget to hire one!

Rich

anonymous Mon, 10/25/2004 - 10:55

radioliver wrote: This is why I assume that Sonarec knows everything about music. How do you live with yourself, it must be hard to live under the constant pressure of being the technical god of music?

If you go to my website and read my background, you'll conclude that I have learned to live with it!

I must assume from your juvenile responses that you DON'T understand why knowing about overtones is critical to both music-making AND music mastering.

And contrary to your snotty assertion, I certainly do not know it all-- no one does.

Rich

anonymous Mon, 10/25/2004 - 11:24

while i feel I must continue to argue, i will stop here because i must admit that i am not of the classical type and that your background was almost fun to read. I just don't like your overly accomplished attitude and your assumptions that someone younger than you is a poor recording engineer. I do not agree to "knowing about overtones is critical to [...] music-making". Music is about feel. It's also about no limitations or rules. Anyways, I'm tired of arguing with you because you feel you know too much. This is a common attitude in the classical domaine. (I thought you'd like a little generalization)

FifthCircle Mon, 10/25/2004 - 21:09

wow... getting a little warm in here. I think it best not to make assumptions about all of the classical folks...

As for the overtone series it was well defined in terms of musical intervals.. Be aware that it also corresponds to 1, 2, 3, 4, etc.. times the fundamental frequency.

Look at the series based on 100 Hz because it is easy to calculate.

100 Hz fundamental. 200 Hz 2nd overtone (a doubling is an octave). 300 Hz 3rd overtone (octave plus a 5th roughly), 400 Hz 4th overtone (2 octaves or 1 octave plus a 5th plus a 4th), etc...

--Ben